Meaning "collection of horses belonging to one stable is attested from 1570s; transferred sense of "group of fighters under same management" is from 1897; that of "group of prostitutes working for the same employer" is from 1937.

For what the grete Stiede Is stole, thanne he taketh hiede, And makth the stable dore fast. [John Gower, "Confessio Amantis," 1390]

adj.

"steadfast, firm," mid-13c., from Old French estable, from Latin stabilis "firm, steadfast," literally "able to stand," from stem of stare "to stand" (see stet). Physical sense of "secure against falling" is recorded from late 14c. Of nuclear isotopes, from 1904.

Not susceptible to a process of decay, such as radioactivity. For example, the most common isotope of carbon, carbon 12, is stable. Protons and photons are examples of stable subatomic particles. See more at decay.

Relating to a chemical compound that does not easily decompose or change into other compounds. Water is an example of a stable compound.

Relating to an atom or chemical element that is unlikely to share electrons with another atom or element.

Not likely to change significantly or to deteriorate suddenly, as an individual's medical condition.